40 CFR 471.23: New source performance standards (NSPS).

Any new source subject to this subpart must achieve the following new source performance standards. The mass of pollutants in the magnesium forming process wastewater shall not exceed the following values:

(a) Rolling spent emulsions.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off/kg (pounds per million off-pounds) of magnesium rolled with emulsions

Chromium 0.028 0.011

Zinc 0.076 0.032

Ammonia 9.95 4.37

Fluoride 4.44 1.97

Oil and grease 0.746 0.746

TSS 1.12 0.895

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(b) Forging spent lubricants—subpart B—NSPS. There shall be no discharge of process wastewater pollutants.

(c) Forging contact cooling water.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off/kg (pounds per million off-pounds) of forged magnesium cooled with water

Chromium 0.107 0.044

Zinc 0.295 0.122

Ammonia 38.5 17.0

Fluoride 17.2 7.63

Oil and grease 2.89 2.89

TSS 4.34 3.47

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(d) Forging equipment cleaning wastewater.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off/kg (pounds per million off-pounds) of magnesium forged

Chromium 0.002 0.0006

Zinc 0.004 0.002

Ammonia 0.532 0.234

Fluoride 0.238 0.106

Oil and grease 0.040 0.040

TSS 0.060 0.048

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(e) Direct chill casting contact cooling water.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off-kg (pounds per million off-pounds) of magnesium cast with direct chill methods

Chromium 1.46 0.593

Zinc 4.03 1.66

Ammonia 527 232

Fluoride 235 105

Oil and grease 39.5 39.5

TSS 59.3 47.4

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(f) Surface treatment spent baths.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off-kg (pounds per million off-pounds) of magnesium surface treated

Chromium 0.173 0.070

Zinc 0.476 0.196

Ammonia 62.1 27.3

Fluoride 27.8 12.3

Oil and grease 4.66 4.66

TSS 6.99 5.60

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times

(g) Surface treatment rinse.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off-kg (pound pers million off-pounds) of magnesium surface treated

Chromium 0.700 0.284

Zinc 1.93 0.794

Ammonia 252 111

Fluoride 113 49

Oil and grease 18.9 18.9

TSS 28.4 22.7

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times

(h) Sawing or grinding spent emulsions.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off-kg (pounds per million off-pounds) of magnesium sawed or ground

Chromium 0.007 0.003

Zinc 0.020 0.008

Ammonia 2.60 1.15

Fluoride 1.16 0.515

Oil and grease 0.195 0.195

TSS 0.293 0.234

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(i) Degreasing spent Solvents—subpart B—NSPS. There shall be no discharge of process wastewater pollutants.

(j) Wet air pollution control scrubber blowdown.

Subpart B—NSPS

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average

mg/off-kg (pounds per million off-pounds) of magnesium sanded and repaired or forged

Chromium 0.229 0.093

Zinc 0.632 0.260

Ammonia 82.5 36.3

Fluoride 36.9 16.4

Oil and grease 6.19 6.19

TSS 9.29 7.43

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.